Im wondering where the difference is in an LS1 and LT1 catback setup. is it just the I pipe thats different? or is the section from the rear axle to the tips different as well? and are the hangers any different? Im wanting to buy a flowmaster catback from someone that came off an LT1. but the thing is my car is an LS1. the only part that Im getting from him is the section from the rear axle to the tail pipes. So I think its the same, am i right????